Vol. I] WILLIAMS— BUTTERFLIES AND HAWK-MOTHS 313 



to net. It is widely distributed in the Archipelago as is the 

 case with its favorite food-plant. An old pupal shell, found on 

 the ground, among the dry leaves of Cordia, on Tower Island, 

 undoubtedly belonged to this species. (About September 15, 

 1906.) This insect was taken on the Albatross Expedition 

 (1889), from Charles Island. There are two males and two 

 females in the Tring Museum, England, and taken by R. H. 

 Beck 3-14-1901. Snodgrass and Heller took it on Hood and 

 Albemarle (Hopkins-Stanford Galapagos Expedition). There 

 are nine males and five females in the Academy's collection. 

 Taken on Charles, Chatham, and Albemarle Islands. 



Alar expanse : $ 74, 82, 84, 85, 88, 89, 89, 90, 92=85.88 

 mm. 



9 82, 92, 98, 102, 103=95.4 mm. Plate XX, fig. 8-9. 



6a. Phlegathontius calapagensis Holland. 

 Aberration nigrita, Rothschild and Jordan, Novitates Zoo- 

 logicae, Suppl., Vol. IX,^ 85, 1903. 



This dark form is thus described by Rothschild and Jordan: 



"A $ from Chatham Island in the Tring Museum is abnormal, having 

 ''he body above and the wings nearly entirely brownish black, except the 

 double series of dorsal dots on the abdomen, the stigma of the forewing 

 and the marginal spots of both wings, which are white, besides feeble traces 

 of white markings on both wings. The first segment of the palpus is much 

 less extended white than in normal specimens. We call this aberrant indi- 

 vidual — ab. nigrita nov." 



I obtained ex larvae, three 2 5 and one $ of nigrita at 

 Tagus Cove, Albemarle Island, end of April, 1906. These 

 four specimens have no yellowish patches but three dirty white 

 ones instead, the first two in the largest 5 , have a shade of 

 brownish yellow however. The double row of abdominal 

 white dots are more or less connected by interspersed white 

 scales. 



This form appears to be quite rare, but its presence would 

 seem to indicate that the variable P. calapagensis may resolve 

 itself into two or more species in the distant future. 



Alar expanse : $ 82 mm. 



5 80, 88, 100=89.33 mm. 



A sphinx larva evidently that of a Phlegathontius, and prob- 

 ably belonging to calapagensis but differing remarkably from 

 and rarer than the usual form of that larva, was taken by me 



